Tail gas treatment system and method of system for producing granular silicon material by silane fluidized bed method

Abstract

The invention provides a tail gas treatment system and method of a system for producing a granular silicon material by a silane fluidized bed method, and the system for producing the granular silicon material by the silane fluidized bed method comprises a silane gas device, a granular silicon material device and a hydrogenation device, the tail gas treatment system comprises a leaching unit which is in fluid connection with the silane gas device, the granular silicon material device and the hydrogenation device and receives tail gas of the silane gas device, the granular silicon material device and the hydrogenation device, one output end of the leaching unit is in fluid connection with the hydrogenation device, and part of treated substances serve as raw materials to be conveyed to the hydrogenation device. The other output end is in fluid connection with the adsorption tank unit; after hydrogen chloride and chlorosilane are removed from an input substance by the adsorption tank unit, the downstream of the adsorption tank unit is connected with the pressure swing adsorption unit; and the pressure swing adsorption unit is used for finally treating the input substances into hydrogen and other tail gases. The tail gas treatment method is realized by adopting the system.

Description

Technical Field

[0001] The invention relates to a tail gas treatment system and method, in particular to a tail gas treatment system and method for a system for producing granular silicon material by a silane fluidized bed method. Background Art

[0002] This section merely provides background information related to the present disclosure and is not necessarily prior art.

[0003] At present, the polysilicon industry has rarely used the technology of producing granular polysilicon by silane fluidized bed method, such as Figure 1 As shown, from the perspective of production and quality, the hydrogen used to push silicon powder from the granular silicon material device replacement product tank, seed crystal tank, silicon powder tank and hydrogenation device high-pressure silicon powder tank contains a portion of nitrogen, so it is generally vented; the replacement hydrogen during the start-up and shutdown of the granular silicon material device and the hydrogenation device is generally vented; the nitrogen content in the circulating hydrogen system of the hydrogenation device is too high, and replacement and venting treatment is also required. Since the circulating hydrogen system contains some chlorosilane, the replacement and venting treatment will also cause chlorosilane and hydrogen loss. The process flow of the existing technology is as follows Figure 1 shown.

[0004] After years of continuous production and operation, it was found that with the increase in production capacity, the amount of hydrogen discharged from the granular silicon material device and the hydrogenation device increased significantly, which caused the multiple electrolyzers of the hydrogen production device to operate at high load or even at full load to meet production needs, which caused a waste of electricity and pushed up production costs.

[0005] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0006] Purpose of the invention: The technical problem to be solved by the present invention is to provide a tail gas treatment system and method for a system for producing granular silicon material by a silane fluidized bed method in view of the deficiencies in the prior art.

[0007] In order to solve the above technical problems, the present invention discloses a tail gas treatment system and method for a system for producing granular silicon material by a silane fluidized bed method, wherein the system for producing granular silicon material by a silane fluidized bed method comprises a silane gas device, a granular silicon material device and a hydrogenation device, and the tail gas treatment system comprises:

[0008] A leaching unit fluidly connected to the silane gas device, the granular silicon material device and the hydrogenation device and receiving the tail gas thereof respectively, wherein one output end of the leaching unit is fluidly connected to the hydrogenation device and returns part of the treated material to the hydrogenation device as a raw material, and the other output end of the leaching unit is fluidly connected to the adsorption tank unit;

[0009] After the adsorption tank unit removes hydrogen chloride and chlorosilane from the input substance, the downstream is connected to the pressure swing adsorption unit;

[0010] The pressure swing adsorption unit finally processes the input material into hydrogen and other tail gases, wherein the hydrogen is sent to the hydrogenation device as a raw material, and the other tail gases are sent to the downstream system for further processing.

[0011] Furthermore, the rinsing unit specifically comprises:

[0012] A filter connected to the granular silicon material device and the hydrogenation device respectively, and the filter is used to filter silicon powder;

[0013] A pressure reducing valve connected to the circulating hydrogen main pipe in the hydrogenation device, which reduces the pressure of hydrogen therein and mixes it with the output end of the filter, and then is connected to the first input end of the second heat exchanger for heat exchange;

[0014] The silane gas device is fluidly connected to the first input end of the first heat exchanger and is used to transport liquid silicon tetrachloride for heat exchange;

[0015] The first output end of the first heat exchanger is fluidically connected to the top feed port of the elution tower to transport the liquid silicon tetrachloride after heat exchange and temperature reduction;

[0016] The bottom feed port of the elution tower is fluidly connected to the first output end of the second heat exchanger, and the gas input from the bottom feed port is mixed and absorbed from bottom to top with the liquid silicon tetrachloride input from the feed port from top to bottom, and the liquid phase material after mixed absorption is discharged from the second output end of the elution tower; the first output end of the elution tower is fluidly connected to the first condenser to condense the unabsorbed gas;

[0017] The gas phase output end of the first condenser is fluidly connected to the second condenser to transfer the gas phase material that has not been condensed into the liquid phase to the second condenser for further condensation;

[0018] The liquid phase output end of the second condenser, the liquid phase output end of the first condenser and the second output end of the elution tower are mixed, and the liquid phase material is transported to the second input end of the first heat exchanger as a refrigerant for heat exchange, and then returned to the hydrogenation device through the second output end of the first heat exchanger as a raw material for processing;

[0019] The substance output from the gas phase output end of the second condenser enters the second condenser through the second input end of the second heat exchanger as a low-temperature gas phase refrigerant for heat exchange, and is then sent to the adsorption tank unit from the second output end of the second heat exchanger.

[0020] Furthermore, the adsorption tank unit specifically comprises:

[0021] Adsorption tanks arranged in parallel.

[0022] Furthermore, the pressure swing adsorption unit specifically comprises:

[0023] A device connected to the output fluid of the adsorption tank unit, wherein the top of the device is connected to the product hydrogen buffer tank fluid, and the bottom of the device is connected to the analytical gas buffer tank fluid via a vacuum pump;

[0024] The product hydrogen buffer tank is used to store product hydrogen and provide it to the hydrogenation device for use;

[0025] The analytical gas buffer tank is used to store other tail gas and provide it to the subsequent tail gas cryogenic treatment system for further processing.

[0026] Furthermore, the filtration accuracy of the filter is 0.01 to 50 μm;

[0027] The pressure reducing valve reduces the pressure to 1-2.5 MPa;

[0028] The first condenser is a tube bundle condenser, wherein the refrigerant temperature is -25 to -45°C;

[0029] The second condenser is a tube bundle condenser, wherein the refrigerant temperature is -70 to -95°C;

[0030] The elution tower is a packed tower, made of low-temperature resistant stainless steel, with a tower diameter of 500-3000 mm and internal packings provided with multiple sections of packings.

[0031] Furthermore, the heat exchange temperature in the second heat exchanger is: 10-45°C at the first input end is exchanged to 5-15°C at the first output end; -70--95°C at the second input end is exchanged to -30--10°C at the second output end;

[0032] The heat exchange temperature in the first heat exchanger is: 30-80°C at the first input end to 5-20°C at the first output end.

[0033] Furthermore, the adsorption tank has a diameter of 100 to 2000 mm and is filled with an adsorbent for adsorbing hydrogen chloride and chlorosilane;

[0034] Furthermore, the device is a programmable valve device or a rotary valve device, and the device comprises an adsorption tower, the interior of which is filled with a solid adsorbent for extracting and storing hydrogen;

[0035] The pressure in the analytical gas buffer tank is ≥10Kpa.

[0036] Furthermore, the number of the adsorption tanks is more than two.

[0037] The present invention also provides a method for treating tail gas of a system for producing granular silicon material by a silane fluidized bed method, which is implemented using the aforementioned system and specifically comprises the following steps:

[0038] Step 1, using the elution unit to receive and process the tail gas from the silane gas device, the granular silicon material device and the hydrogenation device respectively;

[0039] Step 2, the elution unit returns the treated chlorosilane as a raw material to the hydrogenation device, and the uncondensed hydrogen and nitrogen mixed gas, hydrogen chloride and chlorosilane are sent to the adsorption tank unit for treatment;

[0040] Step 3, the adsorption tank unit removes hydrogen chloride and chlorosilane from the input substance and then sends it to the pressure swing adsorption unit for treatment;

[0041] Step 4, the pressure swing adsorption unit finally processes the input hydrogen and nitrogen mixture into hydrogen and other tail gases, wherein the hydrogen is sent to the hydrogenation device as a raw material, and the other tail gases are sent to the downstream system for further processing.

[0042] Beneficial effects:

[0043] 1. The present invention makes full use of materials, recovers and recycles hydrogen and chlorosilane, and reduces the production cost of granular silicon materials.

[0044] 2. The method proposed in the present invention recovers and reduces the loss of hydrogen in the granular silicon material device and the hydrogen in the hydrogenation device to push the silicon powder, as well as the loss of chlorosilane and hydrogen caused by the high nitrogen content in the circulating hydrogen system of the hydrogenation device that needs to be replaced and vented, thereby reducing the load of the electrolytic cell, saving electricity, and recycling materials; reducing the production cost of granular silicon material produced by using a silane fluidized bed. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, and the above and / or other advantages of the present invention will become more clear.

[0046] Figure 1 It is a schematic diagram of the tail gas treatment process in the prior art.

[0047] Figure 2 It is a schematic diagram of the overall flow of the method proposed in the present invention. DETAILED DESCRIPTION

[0048] The present invention provides a method for recycling hydrogen and chlorosilane, which can reduce the loss of hydrogen in the granular silicon material device and the hydrogenation device for pushing silicon powder, and the loss of chlorosilane and hydrogen caused by the high nitrogen content in the circulating hydrogen system of the hydrogenation device, which needs to be replaced and vented, so as to reduce the load of the electrolytic cell, save electricity, and recycle materials; and reduce the production cost of granular silicon material produced by using a silane fluidized bed. The technical solution of the present invention is as follows:

[0049] like Figure 2 As shown, the process method for removing nitrogen from hydrogen and chlorosilane includes a leaching unit, an adsorption tank unit, and a pressure swing adsorption unit (pressure swing adsorption device); wherein the leaching unit mainly consists of: a filter (1), a heat exchanger A (2), a heat exchanger B (3), a leaching tower (4), a condenser A (5), a condenser B (6), a condensate pump (7), and a pressure reducing valve (13); the adsorption tank unit mainly consists of: an adsorption tank AB (8); the pressure swing adsorption unit mainly consists of: a programmable valve or a rotary valve pressure swing adsorption device () (9), a product H2 buffer tank (10), a desorption gas buffer tank (11), and a vacuum pump (12), as follows:

[0050] 1. Effusion unit

[0051] 1.1 First, the hydrogen gas that may contain silicon powder in the granular silicon material device and the hydrogenation device is filtered through a high-precision filter (1) (filtration accuracy 0.01-50 μm) to remove the silicon powder, and the hydrogen gas from the circulating H2 main pipe of the hydrogenation device is decompressed to 1-2.5 MPa through a pressure reducing valve (13), and then merged with the hydrogen gas passing through the filter (1) after the check valve to form a mixed gas. The components of the mixed gas include hydrogen, nitrogen, trichlorosilane, dichlorosilane, hydrogen chloride, etc.;

[0052] 1.2 The mixed gas with a temperature of 10 to 45°C enters the tube side of the heat exchanger B (3), and heat is exchanged between the gas and the low-temperature gas from the condenser B (6) inside the heat exchanger B (3). After the temperature of the mixed gas is reduced to 5 to 15°C, it flows out through the outlet of the tube side of the heat exchanger B (3) and enters the elution tower through the gas phase feed port at the bottom of the elution tower (4);

[0053] 1.3 Liquid silicon tetrachloride at a temperature of 30 to 80°C is delivered through the silane gas device and enters the tube side of the heat exchanger A (2). The liquid in the heat exchanger A (2) exchanges heat with the low-temperature liquid from the condensate pump (7). After the temperature of the liquid silicon tetrachloride is reduced to 5 to 20°C, it flows out through the outlet of the tube side of the heat exchanger A (2) and enters the elution tower (4) through the top feed port.

[0054] 1.4 The elution tower (4) is a packed tower made of low-temperature resistant stainless steel, with a tower diameter of 500 to 3000 mm. The tower internal packing is provided with n sections of metal or non-metal packing;

[0055] Liquid silicon tetrachloride is sprayed from top to bottom at the top feed inlet of the elution tower (4), and mixed gas is fed from bottom to top at the bottom feed inlet. Silicon tetrachloride is used as an absorbent, and the temperature of the absorbent is controlled within a suitable range. The trichlorosilane, dichlorosilane and hydrogen chloride in the mixed gas are fully absorbed on the surface of the filler by the similar compatibility principle of low-temperature condensation, and then flow into the bottom of the elution tower. The mixed gas that is not absorbed in the tower enters the tube side of the condenser A (5) through the top outlet of the elution tower.

[0056] 1.5 Condenser A (5) is a tube bundle type. The shell side of condenser A passes through a refrigerant with a temperature of -25 to -45°C. The unabsorbed mixed gas is condensed into a liquid phase in the tube side of condenser A (5), flows out through the bottom outlet of condenser A, and merges with the bottom liquid outlet pipe of the elution tower (4). A portion of the uncondensed mixed gas flows out through the gas phase outlet of condenser A (5) and enters the tube side of condenser B (6).

[0057] 1.6 Condenser B (6) is of tube bundle type. The refrigerant with a temperature of -70 to -95°C passes through the shell side of condenser B. The mixed gas that is not condensed by condenser A is condensed into liquid phase in the tube side of condenser B (6), flows out through the bottom outlet of condenser B, and merges with the bottom liquid outlet pipe of the elution tower (4).

[0058] The low-temperature liquid phase after the absorption in the elution tower, the condensed liquid phase in the condenser A, and the condensed liquid phase in the condenser B is combined and has a temperature of -30 to -50°C. The liquid phase is transported to the heat exchanger A through the condensate pump (7) as a refrigerant to exchange heat with the liquid silicon tetrachloride. The temperature is heated to 5 to 25°C and then sent back to the hydrogenation device for use as a raw material.

[0059] A portion of the mixed gas that is not condensed in the condenser B (6) flows out through the gas phase outlet of the condenser B (6). At this time, the components of the mixed gas are mainly hydrogen, nitrogen, and a small amount of hydrogen chloride and chlorosilane. At this time, the mixed gas enters the heat exchanger B (3) as a low-temperature gas phase refrigerant and exchanges heat with the gas phase mixed gas. The temperature is raised to -30 to -10°C and then enters the adsorption tank unit.

[0060] 2. Adsorption tank unit

[0061] 2.1 The adsorption tank unit (8) is composed of an adsorption tank A and an adsorption tank B connected in parallel. During operation, the adsorption tanks AB are used as a standby tank. The diameter of the adsorption tank is 100 to 2000 mm. The adsorption tank is filled with a special adsorbent. The principle of selective physical adsorption is used to deeply remove hydrogen chloride and chlorosilane. The special adsorbent in the adsorption tank is non-regenerative and the replacement cycle is 3 to 10 years.

[0062] 2.2 The gas from heat exchanger B enters the adsorption tank from bottom to top. When the mixed gas passes through the special adsorbent in the tank, a small amount of hydrogen chloride and a very small amount of chlorosilane are adsorbed by the adsorbent, and hydrogen and nitrogen flow out from the top outlet of the adsorption tank and enter the device.

[0063] 3. Pressure swing adsorption unit ()

[0064] 3.1 The pressure swing adsorption unit () adopts a vacuum pressure swing adsorption process and is mainly composed of a program-controlled valve or a rotary valve device (9), a product H2 buffer tank (10), a desorption gas buffer tank (11), and a vacuum pump (12).

[0065] 3.2 The adsorption tower in the program-controlled valve or rotary valve device (9) is filled with a special solid adsorbent.

[0066] 3.3 The mixed gas of hydrogen and nitrogen from the adsorption tank AB (8) enters from the bottom of the adsorption tower. The solid adsorbent in the bed of the adsorption tower selectively adsorbs specific components in the mixed gas under high pressure, thereby purifying the product gas. The product hydrogen flows out from the top of the adsorption tower and enters the product H2 buffer tank (10), and is then sent back to the hydrogenation unit for use as a raw material.

[0067] 3.4 When the adsorption tower in the programmable valve or rotary valve device (9) is regenerated, the impurity gas adsorbed on the special solid adsorbent is extracted from the adsorption tower by vacuum pump (12). Since the lower the pressure during the regeneration of the adsorption tower, the more conducive it is to desorption, the pressure of the analytical gas buffer tank (11) needs to be controlled at ≥10Kpa before being sent out of the boundary area into the exhaust gas deep cold treatment system.

[0068] The elution unit of the present invention can recover more than 95% of chlorosilane and fully utilize materials at all levels for heat exchange, thereby reducing energy consumption.

[0069] The adsorption tank unit uses special adsorbents to effectively prevent HCl and chlorosilane from entering the device, thereby achieving full use of high-value adsorbents.

[0070] Pressure swing adsorption can be an adsorption tower controlled by a programmable valve or an adsorption tower controlled by a multi-channel rotary structure valve. Regardless of which form is adopted, the hydrogen recovery rate is more than 95%.

[0071] The comparison results of the recovery effect of hydrogen and chlorosilane using this process are shown in the following table:

[0072] Table 1 Comparison of recovery effects

[0073] project Before using this process After using this process Chlorosilane recovery rate % Not recycled More than 95% Hydrogen recovery rate % Not recycled More than 95% Recovered hydrogen purity / More than 99.9%

[0074] In a specific implementation, the present application provides a computer storage medium and a corresponding data processing unit, wherein the computer storage medium can store a computer program, and when the computer program is executed by the data processing unit, the invention content of the tail gas treatment system and method for producing granular silicon material by a silane fluidized bed method provided by the present invention and some or all steps in each embodiment can be run. The storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM), etc.

[0075] Those skilled in the art can clearly understand that the technical solutions in the embodiments of the present invention can be implemented by means of computer programs and their corresponding general hardware platforms. Based on such an understanding, the technical solutions in the embodiments of the present invention can be essentially or partly contributed to the prior art in the form of computer programs, i.e., software products, which can be stored in a storage medium and include several instructions for enabling a device including a data processing unit (which can be a personal computer, a server, a single-chip microcomputer, an MCU or a network device, etc.) to execute the methods described in various embodiments of the present invention or certain parts of the embodiments.

[0076] The present invention provides a tail gas treatment system and method for a system for producing granular silicon materials by a silane fluidized bed method. There are many methods and ways to implement the technical solution. The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention. All components not specified in this embodiment can be implemented by existing technologies.

Claims

1. A tail gas treatment system for a system for producing granular silicon material by a silane fluidized bed method, wherein the system for producing granular silicon material by a silane fluidized bed method comprises a silane gas device, a granular silicon material device and a hydrogenation device, and is characterized in that: The tail gas treatment system comprises: A leaching unit fluidly connected to the silane gas device, the granular silicon material device and the hydrogenation device and receiving the tail gas thereof respectively, wherein one output end of the leaching unit is fluidly connected to the hydrogenation device and returns part of the treated material to the hydrogenation device as a raw material, and the other output end of the leaching unit is fluidly connected to the adsorption tank unit; After the adsorption tank unit removes hydrogen chloride and chlorosilane from the input substance, the downstream is connected to the pressure swing adsorption unit; The pressure swing adsorption unit finally processes the input material into hydrogen and other tail gases, wherein the hydrogen is sent to the hydrogenation device as a raw material, and the other tail gases are sent to the downstream system for further processing.

2. The tail gas treatment system of a system for producing granular silicon material by a silane fluidized bed method according to claim 1, characterized in that: The elution unit specifically comprises: A filter (1) connected to the granular silicon material device and the hydrogenation device respectively, wherein the filter (1) is used to filter silicon powder; A pressure reducing valve (13) connected to the circulating hydrogen main fluid in the hydrogenation device, decompresses the hydrogen therein and mixes it with the output end of the filter (1), and then is connected to the first input end of the second heat exchanger (3) for heat exchange; The silane gas device is fluidically connected to the first input end of the first heat exchanger (2) for conveying liquid silicon tetrachloride for heat exchange; The first output end of the first heat exchanger (2) is fluidically connected to the top feed port of the elution tower (4) to transport the liquid silicon tetrachloride after heat exchange and temperature reduction; The bottom feed port of the elution tower (4) is fluidically connected to the first output end of the second heat exchanger (3), and the gas input from the bottom feed port is mixed and absorbed from the bottom to the top with the liquid silicon tetrachloride input from the feed port from the top to the bottom, and the liquid phase material after mixed absorption is discharged from the second output end of the elution tower (4); the first output end of the elution tower (4) is fluidically connected to the first condenser (5) to condense the unabsorbed gas; The gas phase output end of the first condenser (5) is fluidically connected to the second condenser (6), and the gas phase material that has not been condensed into the liquid phase is transmitted to the second condenser (6) for further condensation; The liquid phase output end of the second condenser (6), the liquid phase output end of the first condenser (5) and the second output end of the elution tower (4) are mixed, and the liquid phase material is transported to the second input end of the first heat exchanger (2) as a refrigerant for heat exchange through the condensate pump (7), and then returned to the hydrogenation device through the second output end of the first heat exchanger (2) as a raw material for processing; The substance output from the gas phase output end of the second condenser (6) enters the second condenser (6) as a low-temperature gas phase refrigerant through the second input end of the second heat exchanger (3) for heat exchange, and is then sent to the adsorption tank unit from the second output end of the second heat exchanger (3).

3. The tail gas treatment system of a system for producing granular silicon material by a silane fluidized bed method according to claim 2, characterized in that: The adsorption tank unit specifically comprises: Adsorption tanks (8) are arranged in parallel.

4. The tail gas treatment system of a system for producing granular silicon material by a silane fluidized bed method according to claim 3, characterized in that: The pressure swing adsorption unit specifically comprises: A device (9) connected to the output fluid of the adsorption tank unit, wherein the top of the device (9) is connected to the product hydrogen buffer tank (10) and the bottom is connected to the analysis gas buffer tank (11) via a vacuum pump (12); The product hydrogen buffer tank (10) is used to store product hydrogen and provide it to the hydrogenation device for use; The analytical gas buffer tank (11) is used to store other tail gas and provide it to a subsequent tail gas cryogenic treatment system for further treatment.

5. The tail gas treatment system of a system for producing granular silicon material by a silane fluidized bed method according to claim 4, characterized in that: The filtration accuracy of the filter (1) is 0.01 to 50 μm; The pressure reducing valve (13) reduces the pressure to 1-2.5 MPa; The first condenser (5) is a tube bundle condenser, wherein the refrigerant temperature is -25 to -45°C; The second condenser (6) is a tube bundle condenser, wherein the refrigerant temperature is -70 to -95°C; The elution tower (4) is a packed tower, made of low-temperature resistant stainless steel, with a tower diameter of 500 to 3000 mm, and the internal packing is provided with multiple stages of packing.

6. The tail gas treatment system of a system for producing granular silicon material by a silane fluidized bed method according to claim 4, characterized in that: The heat exchange temperature in the second heat exchanger (3) is: 10-45°C at the first input end is exchanged to 5-15°C at the first output end; -70--95°C at the second input end is exchanged to -30--10°C at the second output end; The heat exchange temperature in the first heat exchanger (2) is: 30-80°C at the first input end to 5-20°C at the first output end.

7. The tail gas treatment system of a system for producing granular silicon material by a silane fluidized bed method according to claim 3, characterized in that: The adsorption tank (8) has a diameter of 100 to 2000 mm and is filled with an adsorbent for adsorbing hydrogen chloride and chlorosilane.

8. The tail gas treatment system of a system for producing granular silicon material by a silane fluidized bed method according to claim 4, characterized in that: The device (9) is a programmable valve device or a rotary valve device, and the device (9) comprises an adsorption tower, the interior of which is filled with a solid adsorbent for extracting and storing hydrogen; The pressure in the analytical gas buffer tank (11) is ≥10 Kpa.

9. The tail gas treatment system of a system for producing granular silicon material by a silane fluidized bed method according to claim 3, characterized in that: The number of the adsorption tanks (8) is more than two.

10. A method for treating tail gas in a system for producing granular silicon material by a silane fluidized bed process, characterized in that: Using any system described in claims 1-9 to implement, specifically comprising the following steps: Step 1, using the elution unit to receive and process the tail gas from the silane gas device, the granular silicon material device and the hydrogenation device respectively; Step 2, the elution unit returns the treated chlorosilane as a raw material to the hydrogenation device, and the uncondensed hydrogen and nitrogen mixed gas, hydrogen chloride and chlorosilane are sent to the adsorption tank unit for treatment; Step 3, the adsorption tank unit removes hydrogen chloride and chlorosilane from the input substance and then sends it to the pressure swing adsorption unit for treatment; Step 4, the pressure swing adsorption unit finally processes the input hydrogen and nitrogen mixture into hydrogen and other tail gases, wherein the hydrogen is sent to the hydrogenation device as a raw material, and the other tail gases are sent to the downstream system for further processing.

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